import java.lang.*;
import java.io.*;
public class Sum {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		int a = 10;
		int b = 15;
		int z = a + b;
		System.out.println("Tong cua 10 + 15 = " + z);
		System.out.println("Hieu cua 10 - 15 = " + (10 - 15));
	}

}
